Predicting Thermal Quenching in Inorganic Phosphors

Abstract

We unify two prevailing theories of thermal quenching (TQ) in rare-earth-activated inorganic phosphors -the cross-over and auto-ionization mechanisms -into a single predictive model. Crucially, we have developed computable descriptors for activator environment stability from ab initio molecular dynamics simulations to predict TQ under the cross-over mechanism, which can be augmented by a band gap calculation to account for auto-ionization. The resulting TQ model predicts the experimental TQ in 29 known phosphors to within ~ 10-11%. Finally, we have developed an efficient topological approach to rapidly screen vast chemical spaces for the discovery of novel, thermally robust phosphors.

Halide Perovskite Nanocrystal Emitters

“…In general, the emission intensity of luminescent materials progressively decreases with increasing temperature, and this phenomenon is known as emission thermal quenching (TQ). [ 141 ] Backlit displays for LCD applications typically operate at 40–50 °C, [ 142 ] and the operating temperature can reach as high as 200 °C in the case of high‐power phosphor‐converted LEDs. [ 141 ] Therefore, emission TQ is one of the crucial phenomena that strongly affects the performance of luminescent materials toward various luminescence‐based applications.…”

“…[ 141 ] Backlit displays for LCD applications typically operate at 40–50 °C, [ 142 ] and the operating temperature can reach as high as 200 °C in the case of high‐power phosphor‐converted LEDs. [ 141 ] Therefore, emission TQ is one of the crucial phenomena that strongly affects the performance of luminescent materials toward various luminescence‐based applications. Materials with a robust crystal structure, such as rigid inorganic phosphors, exhibit a low‐emission TQ intensity.…”

“…Materials with a robust crystal structure, such as rigid inorganic phosphors, exhibit a low‐emission TQ intensity. [ 141 ]…”

Suppression of Eu2+ Luminescence Loss

“…[ 44b,45 ] As shown in the diagram, the small S indicates a limited offset between Eu 2+ 4f and 5d potential energy surfaces, [ 46 ] (Figure 4b) which prevents the de‐excitation of Eu 2+ 5d electron through the crossover pathway. [ 47 ] Overall, the nonradiative relaxation processes are strongly suppressed in the system, hence the high luminescence efficiency of Eu 2+ ‐doped SMPO with remarkable thermal stability is acquired (Figure 4c).…”

An Integrated Luminescent Information Encryption–Decryption and Anticounterfeiting Chip Based on Laser Induced Graphene

“…Figure 2c–f presents the temperature dependence of PL and LPL spectra under the excitation of 240 nm. As shown in Figure 2c,d, the PL spectrum of SCGO:0.03 Zn 2+ reveals a single broad blue emission band at 410 nm which decreases dramatically at 333 K owing to thermal quenching (Figure S5a, Supporting Information), [ 54–56 ] the LPL quenches completely at 413 K (Figure S5b, Supporting Information). Meanwhile, Figure 2e,f exhibits the PL and LPL intensity change of SCGO:0.01Nd 3+ at high‐temperature.…”